Monitoring of various parameters and conditions downhole during drilling operations is important in locating and retrieving hydrocarbons, such as oil and gas, there from. Such monitoring of the parameters and conditions downhole is commonly defined as “logging”. Boreholes are drilled through various formations at different levels of temperature/pressure to locate and retrieve these hydrocarbons. Accordingly, a number of different sensors are used to monitor the parameters and conditions downhole, including the temperature and pressure, the various characteristics of the subsurface formations (such as resistivity, porosity, etc.), the characteristics of the borehole (e.g., size, shape, etc.), etc. Such sensors may include electromagnetic propagation sensors, nuclear sensors, acoustic sensors, pressure sensors, temperature sensors, etc. The data generated from the measurements by these sensors can become voluminous (e.g., data related to sonic and imaging information).
Typically, such data may initially be stored in various components downhole. The data is then downloaded from these components to a computing device on the surface for analysis and possible modifications to the current drilling operations. A current approach for downloading and downloading of this data includes the use of low data rate electrical connections after the downhole drilling tools are pulled out of the borehole. Two different types of communications are typically used for such retrieval. A first type includes a communication having a transformer with a single ended data signal. However, this type of communication typically has a low data rate (e.g., less than 50 kilobits per second) because of the transformer selections and high capacitive loading presented at the tools and cables. Additionally, the single ended data signal is sensitive to different noise sources (such as ground noise) that are coupled to the wires used for communication. A second type of communication provides for differential signaling using RS-485 drivers and receivers. However, the data rate for this second type of communication is usually limited to approximately two-four megabits/second at approximately 1000 feet. Moreover, these two different approaches could not operate at an acceptable data rate in a Class I, Division 1 Area, Zone 0 or Zone 1 on the drilling floor because of the hazardous risks associated with the electrical connections in an ambient gaseous environment that may include combustible gases. Data rates about 100 megabits are usually difficult to be intrinsic safely protected using barriers.